Radiotelegraphy signaling system



7 H. ELLIOTT RADIOTELEGRAPHY SIGNALING SYSTEM Filed Aug. 25 1921 2 Sheets-Sheet 1 I BY %9 ATTORNEYS Nov. 6, 1 923. 1,4733% H. F. ELLIOTT RADIOTELEGRAPHY SIGNALING SYSTEM Filed Aug. 23. 1921' 2 Sheets-Sheet 2 WITNESS INVENTOR A TTORNE YS Patented Nov. 6, 1923.

earn warren stares rarest same HAROLD F. ELLIOTT, OF PALO ALTO, CALIFORNIA, ASSIGNOIR- TO AUGUSTUS TAYLOR, OF SAN FRANCISCO, CALIFORNIA.

RADIOTELEGRAPHY SIGNALING SYSTEM.

Application filed August 23, 1921. Serial No. 494,468.

To all whom it may concern:

Be it known that I, HAROLD F. ELLIOTT, a citizen of the United States, and a resident of Palo Alto, Santa Clara County, State of California, have invented a certain new and useful Radiotelegraphy Signaling System, of which the following is a specification.

The invention relates to radio telegraphy signaling systems and particularly to a signaling system for use in connection with high power transmitting stations.

An object of the invention is to provide an efiicient and efiective signaling system for high power radio transmission stations.

Another object of the invention is to provide a uniwave signaling system for high power stations.

The invention possesses other advantageous features, some of which, with the foregoing, will be set forth at length in the following description, where I shall outline in full, those forms of the invention which I have selected for illustration in the drawings accompanying and forming part of the present specification. In said drawings I have shown several transmission systems embodying my invention, but it is to be understood that I do not limit myself to such forms, since the invention, as set forth in the claims, may be embodied in a plurality of other forms.

Referrlng to said drawings:

Fig. 1 is a diagrammatic representation of a uniwave signaling system embodying'my invention and characterized by an untuned loop system.

Fig. 2 is a diagrammatic representation of a modified form of one signaling circuit.

Fig. 3 is a diagrammatic representation of 40 a uniwave signaling system of my invention,

comprising a tuned loop system.

Fig. 4 is a diagrammatic representation of a transmission system embodying'my invention and employing an alternator as the source of radio frequency current.

Fig. 5 is a diagrammatic representation of a modified form of the system.

The system of my invention is particu-.

larly applicable to a continuous wave transmitting system and in the present embodiment I have shown it used in connection with a continuous wave arc generator 3 of the Poulsen type, but it is to be understood that it may be employed with other constant frequency generators ofradio frequency current. One side of the arc is grounded and the other side is connected to the antenna 4, through one winding of the transformer 5 and the inductance or main loading coil 6. When the system of this invention is used in connection with an arc radio generator in a uniwave signaling system, a non-radiating oscillatory circuit 7 containing the other winding of the transformer 5, an inductance coil 8, a capacity 9 and a variable resistor 12, is connected across the arc, but this non-radiating circuit may be omitted when an alternator or other constant frequency generator of radio frequency current is used. v

In an are system, means are provided for varying the impedances of the antenna circuit and the non-radiating circuit, so that the arc will be caused to oscillate on one circuit to the practical neglect of the other. These means are usually operatively connected together, so that the impedances of the two circuits are varied simultaneously and oppositely. Inductively coupled to the inductor 6 by the loop 1.3 is a signaling cir cuit containing a plurality of voltage equalizing reactors 14 connected in series. Con.- nected around each reactor 14L is a key cir-- cuit containing a resistor 15 and key contacts l6. Inductively coupled to the inductor 8 by the loop 17 is a signaling circuit containing a plurality of voltage equalizing reactors 18 connected in series. Connected around each reactor 18 is a key circuit containing a resistor 19 and key contacts '21. The key contacts 16 and 21 are grouped at convenient points near the loading inductors 6 and 8 and are preferably operatively connected together, either mechanically or electrically, so that when the contacts 16 are opened, the contacts 21 are closed, and vice versa. In Fig. 1 I have shown the contacts mechanically connected by a bar 22, but in practice solenoids will be employed for moving the contacts. The signaling circuits containing the loops 13 and 17 may be inductively associated with any suitable portions of the main circuits, or may be directly coupled to the main circuits by connecting the signaling circuits directly across or in to portions of the main circuits. In theory, any method of connection may be used in which the operation of the keys serve to vary the constants of the main circuits,

but in practice, the inductive coupling is negligible mutual coupling; When the key contacts are closed, the reactors are shunted by the resistors, whose impedance islow' compared with that of the reactors them selves, and most of the current in the loop circuit flows through the resistors. This re-' sults in a change in the impedance-of the main circuit with which theloop is coupled and signaling is accomplished by'epening and closing the keys connected to theme circuits. Thisaction, wherein one set'ot key contactsis opened and, the other is closed, changes'the values of the iin 'aedances of 'tl'ie two'maii'i circuits, that is the antenna circiiitand the: non-radiating circuits, simultaneously and opfiiositely, causing the radio frequencycurrentto oscillate on one circuit to the practical neglect of the other.

Each loop circuit is grounded at points of equal potential, such as at the center of the loop, and at the center of the group of reactors; to carry off the charging currents and to limit the voltage above earth which exists at thekey contacts. The proper installation of these ground connections and their arrangement'so'that additional voltage is not induced at the key contacts ,by the charging current are important-features of this untuned loop system.

Instead of arranging the resistors in the key circuits and in shunt with relation to the reactors, resistors'23; may be connected directly in the loop circuits as shown in Fig. 2, although under certain conditions this may add appreciably to the resistances of themain circuits,

In Fig. 3 I have shown a modified form of the system used in connection with an arc in which the loop'circuits are tuned to resonance at the frequency of operation when the keys are closed. In this system, the circuits of the keys and resistors are connected to the loop circuits through transformers 24. Each 100 circuit is provided with means for tuning the circuit to resonance, and this means preferably comprises a capacitance 25 and an inductor 26, in each leg "of the loop circuit. This tuning reduces to Zero the reactance ofthe loop circuit and makes it possible to secure minimum residual current in the circuit on whichthe are is not oscillating.

.When the keys associated with a loop-circuit are" closed, there is a large change in the impedance of the main oscillatory circuit to which tho tuned loopis coupled with a rescarce; an oscillator nonradia said loop circuit; and key around said reactdrs.

sultant reduction of the residual current therein to a small value;

By properly winding the transformers 24,

the current-voltage duty on the key contacts may be adjusted to obtain the Values which giyebest operation, and by properly insulating the windings of the transformers, one contact of each key may be grounded, which is desirable with certain types of keys.

- Instead'ofusing transformers, the keys may be connected directly around the reactors, as shown in Fig. 1, or they may be connected in any manner which will cause their opening and closing to alternately tune and detune the loop with which they are associated The'resistors may be connected directly in the loop, as shown in Fig. 2, and

the loop circuit should be grounded as set nected to the loading coil 6' of the antenna circuit, by the loop l3,but the signaling circuit may be directly connected to the loading coil or to other parts of the antenna circuit, as shown in Fig. 5, or may be directly connected into the antenna circuitj Signaling circuits such 'as heretofore described may also be used for Varying the int pedance of only one main circuit when the source of radio frequency oscillations is either of constant or yarn ble frequency and a non-radiating or second main circuit is or is not used; i

'While I have particularly described the application of the present invention to an uni-wave signaling system, it is understood that'it may be' emplcyed in other signaling systein's,wherein it is desirable to di'iude the l'oa'd'a'ta high power station among a plurality of; key contacts. The loop'sy'stein 'described herein may be advantageously enip'loy'ed wherever ijt i's desirable to yary the constants of a circuit for signaling purposes. Icl'aiini 1. In a r'adio' -telegraphy signaling system, a source of radio frequency current. oscillatory radiating circuit connected. to said g "circuit connected to said source, a loop circuit inductii "ely coupled to one cf said oscillatory circuits, plurality of reactors in series in circuits? cdnnect'e'd 2. In a radio telegraphysignaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, an oscillatory non-radiating circuit connected to said source, a loop circuit inductively coupled to one of said oscillatory circuits, a plurality of reactors in series in said loop circuit, and means for varying the impedance of said loop circuit.

3. In a radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, an oscillatory non-radiating circuit connected to said source, a loop circuit in ductively coupled to one of said oscillatory circuits,a plurality of reactors in series in said loop circuit, and acircuit containing a key and a resistor connected around each reactor.

4. In a radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, an oscillatory non-radiating circuit connected to said source, a loop circuit inductively coupled to one of said oscillatory circuits, a plurality of reactors in series in said loop circuit, key circuits connected around said reactors and means for simultaneously operating all of said keys.

5. In a radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, an oscillatory non-radiating circuit connected to said source, a loop circuit inductively coupled to one of said oscillatory circuits, a plurality of reactors in series in said loop circuit, a circuit containing a key and a resistor connected around each reactor and means for simultaneously operating all of said keys.

6. In a radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, an oscillatory non-radiating circuit connected to said source, a loop circuit inductively coupled to one of said oscillatory circuits, plurality of reactors in series in said loop circuit, means for varying the impedance of the loop circuit and means connecting the loop circuit to earth at points of equal potential.

7. In a radio-telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, an oscillatory non-radiating circuit connected to said source, a loop circuit inductively coupled to each oscillatory circuit, a plurality of reactors in series in each loop circuit and means for oppositely varying the impedances of said loop circuits.

8. In a radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, an oscillatory non-radiating circuit connected to said source, a loop circuit inductively coupled to each oscillatory circuit, a plurality of reactors in series in each loop circuit, and means for simultaneously and oppositely varying the impedances of said loop circuits. 1 v

9. In a radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, an oscillatory non-radiating circuit connected to said source, a loop circuit inductively coupled to each oscillatory circuit, a plurality of reactors in series in each loop circuit and key circuits connected around said reactors.

10. In a radio telegraphy signaling system, a source of radio frequency current, an

oscillatory radiating circuit connected to said source, an oscillatory non-radiating circuit connected to said source, a loop cir cuit inductively coupled to each oscillatory circuit, a plurality of reactors in series in each loop circuit and a circuit containing a key and a resistor connected around each reactor.

11. In a radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit. connected to said source, an oscillatory non-radiating circuit connected to said source, a loop circuit inductively coupled to each oscillatory circuit, a plurality of reactors in series in each loop circuit, a circuit containin a key and a resistor connected around each reactor and means for simultaneously operating all of said keys.

12. In a radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, an oscillatory non-radiating circuit connected to said source, a loop circuit inductively coupled to each oscillatory circuit, a plurality of reactors in series in each loop circuit, means for oppositely varying the: impedances of the loop circuits and means connecting each loop circuit to earth at points of equal potential.

13. In a radio tclegraphy signaling system a source of radio fre uenc current an a 3 oscillatory radiating circuit connected to said source, an oscillatory nonradiating circuit connected to said source, a loop circuit tuned to resonance at the frequency of operation inductively connected to one of said circuits and signaling means for varying the in'ipedence of the loop circuit.

14;. In a radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, an oscillatory non-radiating circuit connected to said source, a loop cir cuit tuned to resonance at the frequency of operation inductively connected to one of said circuits and signaling means for detuning said loop circuit.

15. In a radio telegraphy signaling syssaid source, an oscillatory non-radiating circuit connected to said source, a 'loop circuit tuned to resonance at the frequency of operation inductively connected to one of said =c1rcu ts,:, a plurality ofvreactors in series 1n said loop circuit and key circuits connected around said reactors.

16. In a radio telegraphy signaling sys tem, a source of radio frequency current, an oscillatory radiating circuit connected to said source, an oscillatory non radiating circuit connected to said source, a loop circuit tuned'to resonance at the frequency of operation inductively connected to one of said circuits, a plurality of reactors in series in said loop circuit, key circuits connected around said reactors and means for SlIIlHltaneously operating all of saidkeys.

17. In a radio telegraphy signaling systern, a source of radio frequency current, an

oscillatory radiating circuit connected to said source, an oscillatory non-radiating circuit connected to said source, a loop circuit tuned to resonance at the frequency of operation inductively connected to one, of said circuits, reactors in series in the loop circuit, a circuit containing a key and a resistor connected around each reactor, and means for simultaneously operating all of said keys.

18. Ina radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, an oscillatory non-radiating cir cuit connected to said source, a loop circuit tuned to resonance at the frequency of-operation inductively connected to one of said circuits, means for varying the impedance of the loop circuit and means connecting the loop circuit to earth at points of equal potential;

19. In a radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, an oscillatory non-radiatingcircuit connected to said source, a loop circuit tuned to resonance at the frequency of oper ation inductively connected to' one of said circuits, a plurality of reactors in series in said loop circuit, and a key' associated with each reactor, said loop circuit being in resonance when the keys are closed.

20. In a radio telegraphy signaling system, a source of radio frequency curi 'ent, an oscillatory radiating circuit connected to said source, an oscillatory non-radiating circuit connected to said source, a loop circuit i tuned to resonance at the frequency of operation inductively connected to each of said circuits, and means for oppositely varying the impedances of said loop circuits.

21. In a radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, an oscillatory non-radiating circuit connected to said source, a loop circuit tuned to resonance at 'thejfrequency of operation inductively connected to each .of said circuits, and means for simultaneously and oppositely varying the impedances of said loop circuits. 7

225111 a radio telegraphy'signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, an oscillatory non-radiating cir cuit connected to said source, a loop circuit tuned to resonance at the frequency of operation inductively connected to each of said circuits, a plurality of reactors in series in each loop circuit and key circuits connected around said reactors,

23. In a radio telegraphy signaling sys tern, a source of radio frequency current, an oscillatory radiating circuit connected to said source, an oscillatory non-radiating circuit connected to said source, a loop'circuit tuned to resonance at the frequency of oper ation inductively connected to each of said circuits, a plurality of reactors in series in each loop circuit and a circuit containing a key and a resistor connected around each reactor. r V

Qt. In a radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, an oscillatory non-radiating circuit connected to said source, a loop circuit tuned to, resonance at the frequency of operation inductively connected to each of said circuits, a plurality of reactors in series in.

said source, an oscillatorynon-radiating circuit connected to said source, a loop circuit tuned to resonance at the frequency of operationinductively connected to each of said circuits, a plurality of reactors in series in each loop circuit, a circuit containing a key and a resistor connected around each re-f actor, and means for simultaneouslyopening the keys associated with one circuit and closing the keys associated with the other cir cuit. V

26. In a radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, an oscillatory nonra dieting circuit connected to said source, a loop circuit tuned to resonance at the frequency of operation inductively connected to each of said circuits, means for oppositely varying the impedances of said loop circuits and means connecting each loop. circuit to earth at points of equal'potential. k

27. In a radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, an oscillatory non-radiating circuit connected to said source, a loop circuit tuned to resonance at the frequency of operation inductively connected to each of said circuits, a plurality of reactors in series in each loop circuit, and a key associated with each reactor, each loop circuit being in resonance when the keys associated therewith are closed.

28. In a radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, a loop circuit inductively coupled to said circuit, a plurality of reactors in series in said loop circuit and key circuits connected around said reactors.

29. In a radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, a circuit connected to said radiating circuit, a plurality of reactors in se rie in said connected circuit and key circuits connected around said reactors,

30. In a radio trannsmitting system, a source of radio frequency current, a radiating circuit connected to said source, and means for varying the constants of the radiating circuit, comprising a plurality of independent reactors, means for so connecting these reactors to the radiating circuit that radio frequency current from the source may flow through them in series, and means for varying the impendances of the reactors.

31. In a radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, a circuit connected to said radiating circuit, a plurality of reactors in series in said connected circuit, and a circuit containing a key and a resistor connected around each reactor.

32. In a 'radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, a circuit connected to said radiating circuit, a plurality of reactors in series in said connected circuit, key circuits connected around said reactors, and means for simultaneously operating all of said keys.

33. In a radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, a circuit connected to said radiating circuit, a plurality of reactors in series in said connected circuit, a circuit containing a key and a resistor connected around each reactor, and means for simul taneously operating all of said keys.

34. In a radio telegraphy signaling system, a source of radio frequency current, an

te l

oscillatory radiating circuit connected to said source, a circuit inductively connected to said radiating circuit, a plurality of re actors in series in said connected circuit, means for varying the impedance of the connected circuit and means connecting the connected circuit to earth at points of equal potential.

35. In a radio transmitting ystem, a source of radio frequency current, a radiating circuit connected to said source, and means for varying the constants of the radiating circuit, comprising a circuit tuned to the frequency of operation, means for connecting said circuit so as to parallel a portion of the radiatin circuit impedance, and a variable reactor in series with the tuned circuit.

36. In a radio telegraphy signaling systern, a source of radio frequency curent, a oscillatory radiating circuit connected to said source, a circuit tuned to resonance at the frequency of operation connected to said radiating circuit, a plurality of reactors in series in said connected circuit and key circuits connected around said reactors.

37. In a radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, a circuit tuned to resonance at the frequency of operation connected to said radiating circuit, a plurality of reactors in series in said connected circuit and a circuit containing a key and a resistor connected to each reactor.

:58. In a radio transmitting system a source of radio frequency current, a radiating circuit connected to said source, and means for varying the constants of the radiating circuit, comprising a circuit tuned to the frequency of operation and inductively coupled to a portion of the radiating circuit impedance, and a variable reactor in series with the tuned circuit.

39. In a radio telegraphy signaling system, a source of radio frequency current, an oscillatory radiating circuit connected to said source, a loop circuit tuned to resonance at the frequency of operation inductively connected to said radiating circuit, a pluraiity of reactors in series in said loop circuit and keys connected around said reactors.

ed). In a radio telegraphy signaling systern, a source ofradio frequency current, an oscillatory radiating circuit connected to said source, a loop circuit tuned to resonance at the frequency of operation inductively connected to said radiating circuit, a plurality of reactors in series in said loop circuit and a circuit containing a key and a resistor connected to each reactor.

In testimony whereof, I have hereunto set my hand.

HAROLD F. ELLIOTT. 

